On the phone from Erbil in Kurdistan, I asked him how many areas of Iraq were now extremely dangerous to live in.

JEFF BATES: Aside from the Kurdistan region, which remains relatively safe, and actually it's quite safe, most of Iraq right now is in a very unstable situation.

The south, near Basra, is still reportedly fairly calm. We're hearing about a lot of violence that's happening in certain parts of Iraq, but it changes. And as I said before, a lot of this is unverified in the sense that we may get something posted on Facebook by ISI (Islamic State in Iraq), which we don't know if it's propaganda. We get reports from people who claim to have seen things. And what we're trying to do is get personal, firsthand accounts from the families who've been displaced as to what they've undergone.

But, in essence, most of Iraq outside of Kurdistan and certain parts of the south are in flux right now. And the situation is critical.

MARK COLVIN: And how dangerous are the cities that ISIS has actually captured?

JEFF BATES: We understand that in some of these places they've returned to relative calm. People have returned. Some of the people who've returned haven't liked what they've seen and have left again. Some of the people have reintegrated.

It seems that ISIS is trying to win the hearts and minds. So once they go in, and in many cases it seems as if they've gone in really without much of a fight, they stabilise fairly quickly. Whether or not they're able to get systems up and running fully, you know we're trying to verify that - for example, hospitals, medical facilities. We get some inputs that say, yes hospitals are running, but then a contradictory report will come in and say they're not running.

But because we're not able to get in and actually assess at this point, it's hard for us to say one way or the other. So we're assuming, in worst case scenario situations, that there are many families, children, who are not getting access to vital services.

MARK COLVIN: What areas and cities do you think they are controlling now?

JEFF BATES: They're controlling south of the Kurdistan region, and, I would say, west of Baghdad - most of the country.

MARK COLVIN: They issued a decree saying that women shouldn't go out unless absolutely necessary, and saying that they were going to destroy graves and shrines. How worried are you about the kind of destruction and the kind of conditions that they will impose on people?

JEFF BATES: Some of the conditions that they would impose on people - for example, if girls are denied the right to education, you know that's a very serious concern; if children are denied the right to humanitarian access, that's a grave violation of their rights.

So what we're looking at is primarily trying to establish the resolve amongst all actors in Iraq to ensure that the child's rights are still maintained no matter what political power or sectarian influence comes into place.

MARK COLVIN: To what extent are you worried that, for children and adults, this is going to result in a refugee crisis?

JEFF BATES: An IDP crisis, or an internally displaced persons' crisis, a slight variation on the term. But yes, right now, if we go by government figures, about 500,000 people initially fled Mosul. Now, how many have returned we don't know, because they were enumerating people as they left, but not counting as they came back. If we combine that with the Anbar situation, which erupted months back, leading to nearly 500,000 people being displaced, we could be looking at up to a million people.

MARK COLVIN: You've already been battling for a long time with huge problems in Syria, and with a lot of children forced out of Syria, away from their homes in Syria and out of the country into countries like Lebanon and Jordan; how much more of a burden is this going to be? At what stage do you get the straw that breaks the camel's back in terms of aid for children?

JEFF BATES: Well that's a good question. We've internally not seen Iraq so much as individual emergencies. We've been looking at them as, you know, a combination of emergencies that encompasses most of Iraq. So we have a polio outbreak, we have the Anbar crisis, we have the Syrian refugee crisis, each of which requires separate interventions.

One of the narratives that we have, you know, been trying to push in the international community is that Iraq is a very, was a very fragile country, and that it needed to be viewed as such. Now as a high, middle income country, it's hard to attract donor attention, it's hard to attract the humanitarian attention outside of isolated emergencies. So what this situation is, it's helped to reinforce what we've been trying to say - that Iraq needs a lot more, and a lot broader, assistance.

We hope that we will be able to marshal this type of assistance. And the first, initial response from the humanitarian community, the donors and governments around the world, has been one of open generosity. So we've started to see a lot more support coming in both in terms of financial and human resource support. We're seeing the Kurdistan government has opened up their boarders to allow people to come in.

I guess to answer your question, it's very concerning, but it doesn't really change much in terms of what we were expecting and the way we were operating.